Sewing machine



Feb. 22,11944. A, B. CLAYTON SEWING MACHINE Filed June 20, 1942 5sheet-sheet 1 Feb. 22, 1944.`

A. B. CLAYTON SEWING yMACHINE Filed June zo, 1942 5 Sheets-Sheet 2 Feb.22, 1944. A. B. CLAYTON SEWING MACHINE Filed June 20, 1942 3Sheets-Sheet 3 Patented Feb. 22, 1944 UNITED STATES PATENT OFFICE SingerManufacturing Company,

Elizabeth,

N. J., a corporation of New Jersey Application June 20, 1942, Serial No.447,748

ICl. 112-199) 12 Claims.

This invention relates to sewing machines and more particularly tosingle-thread chain-stitch sewing machine mechanisms for driving anoscillatory loop-taker or looper.

A primary object of this invention is to provide an extremely high speedlooper-actuating mechanism for single-thread chain-stitch sewingmachines, whereby the looper has a prolonged dwell prior to thebeginning of its loop-seizing movement. By thus providing a dwell in thelooper, the needle will be given time to properly throw out itsneedle-loop for certain seizure by the looper. It is a further object ofthe invention to accelerate the retracting motion of the looper tohasten the shedding of the needle-loop after the needle has entered it.

Another object of the invention is to provide a particularly compact andlight weight looperactuating mechanism of which all of the elements havebeen designed so that they may be readily applied to and removed fromthe sewing machine by the use of the simplest tools and in a shortperiod of time. By thus providing a quickly applicable looper-actuatingmechanism, the manufacture and assembly of the sewing machine is greatlyfacilitated. Furthermore, the machine as thus made facilitates anyrepair work which may be required during the life thereof.

With the above and other objects in View, as will hereinafter appear,the invention comprises the devices, combinations and arrangements ofparts hereinafter set forth and illustrated in the accompanying drawingsof a preferred embodiment of the invention, from which the severalfeatures of the invention and the advantages attained thereby will bereadily understood by those skilled in the art.

Referring to the drawings,

Fig. 1 is a iront side elevation of a sewing machine incorporating thepresent invention and showing the base portion of the machine insection.

Fig. 2 is a bottom plan view of the present machine.

Fig. 3 is a vertical section taken substantially along line 3-3 of Fig.1.

Fig. 4 is a bottom perspective view of a portion of the looper-actuatingmechanism shown in Fig. 2.

Fig. 5 is a top plan view of the mechanism shown in Fig. 4.

Fig. 6 is an enlarged view in side elevation of one of the looperelements as it enters the needleloop.

' Figs. 7 to 10, inclusive, are sections taken substantially along line1 1 of Fig. 5 and illustrate various stages of movement of the looperactuating mechanism during the stitching cycle.

The sewing machine herewith illustrated as incorporating the presentinvention comprises a frame including a base I5 providing'a cloth-plateIG from one end of which rises the standard Il carrying the overhangingbracket-arm I8 terminating at its free end in the head I9. J ournaled inthe head I9 are the usual presser-bar 2S and endwise reciprocatoryneedle-bar 2| carrying the needles 22. The presser-bar 2U carries theusual presser-foot 23 with which the usual feed-Clog 24 cooperates tofeed the work.

The bed I5 is closed at the bottom by means of a drip-pan 25 having anoil-sump portion 26 provided therein.

The needle-bar 2l has the usual link connection 21 with a crank 28 onthe main shaft 29 journaled in the bracket-arm I8 and carrying thebalance wheel and belt-pulley 33.

Carried by the main shaft 29 is a gear 3i meshing with a gear 3l mountedon a vertical shaft 32 which is suitably journaled in the standard Il.The lower portion of shaft 32 carries a gear 33 meshing with a gear 34mounted upon the rear end portion of a shaft 35 which is horizontallyjournaled in bearings 36 and 3l carried by the base I5 of the frame. Asgears 3| and 34 are of one set size and gears 3| and 33 are or" anotherset size the rotation of the shaft 29 Will rotate shaft 35 in one to onerelation therewith.

The lower end of shaft 32 extends into an oil pump unit 38 and therotation of this shaft is effective to operate the pump so that oilcontained in the oil sump 26 will be drawn up through the pump screen 39and forced through the oil conduits 40, 4I and 42. Conduit 42 circulatesthe oil into the overhanging bracket-arm of the machine and conduits 4|and 4i! conduct the oil to bearings 3l and 43 respectively. For a moredetailed disclosure of this oil pump, reference may be made to the U. S.patent to Kaier, No. 2,206,285, July 2, 1940.

Eccentrics 44 and 45, carried by the shaft 29 are embraced,respectively, by the pitmans 4S and 4l of which the lower portions arerespectively pivotally secured to cranks 48 and 49. Rotation of theshaft 29 will, through the medium of the above notedeccentrics andpitmans, oscillate the two cranks 48 and 49. The crank 48 is secured tothe feed advance and return rockshaft 50, which is suitably mounted inthe base I5 and connected at its forward end to the usual feed-bar 5Icarrying the feed-dog 24. The crank i9 is secured to the feed-liftrock-shaft 52 also mounted in the base l and operativeiy connected tothe feed-bar 5|. For a more complete disclosure of this feedingmechanism reference may ae made to the above noted Kaier patent.

As may be best seen in Figs. 1 and 5, the base l5 is provided with anaperture 53 for receiving the bearing 31 which is secured therein bymeans of a set screw 55. Upon an extended end portion of the bearing 31is mounted a substantially horizontally C-shaped bracket 55 securedthereto by means of set screws 56. Each arm portion of the racket 55 isprovided with a semi-circular recess 5l for supporting a hanged bearing58 retained by means of a bearing-cap 59 'scour-edito each arm by meansof screws 6i). -Sli'dably mounted within the two flanged bearings 58 isan endwise reciprocatory rod 61 which is ldisposed in a directionparallel to the linejof feed and parallel to the plane of thecloth-plate l5.

The rod'i! yis ralso'disposed horizontally transverse to the bed-shaftv35 whereby the'lon'gitudh nal axesof 'said shaft and saidfrod are"insubstantially the same horizontal plane. Intermediate its ends, `therod 6l isprovided'witha guideway or channel'SZ lengthwise extending atright angles tothe longitudinal axis ofthe rod 6 l. Depending from theguideway '62 is a 'member 63 having a slot Ell formedtherein'for'ernbracing a stub-rod E5 for the purpose ofvpreventingtuming of the rodl about its longitudinal'axis. The stub-rodis rigidlysecured within the'oppce site arm'portions of ajholder B5by'mean's ofset screws ti. The holder'tis in'tur'ns'ecuredfto the hubportionof bracket 55vby v'a screw 5S. Asmay be seen in Fig. il, the backsidey of the guideway portion of the rod 6l is providedwith "a Apair ofapertures'for'thesole'purpose of'making'for a lighter reciprocatingunit. l

As may be best "seen Yin Fig. 5, the shaft 35 1s journaled withinthebearing 3T and itextends therethrough to have mounted upon itsendportion'a rotary disk-crank ES'whichi's secured vto the shaft Aby means of asetscrew 1t. Extending from'the forwardfaceof the `rotary crank 't9 is acrank-pin ltembraced'by a-wear`or jslideblock l2 which snuglyenterstheguideway 63.

As hereinabove described, the ,shaft 35 is given a one to'onerotary`motion with'the shaft`2'5. The crank-pin 'H and Vthe slide-block "I2are therefore given a rotary motionwhich imparts pure simple harmonicreciprocatory ``movements to the rodl. Figs. 8 and v10 show,respectively, the left andright'handdead-center points" o f theslide-block l2 relative Vto the guideway 52. It is to `be understoodthat the 'rodl 4k'comes to lrest momentarily whenever the' slide-'blockis in either of its two deadcenterpositions, 'and further,`that the rod6l attains its-greatest"velocitywhenever the slide-'block'passes through'eithe'r'of its two positions medianly of -the dead#centerpoints.`

Extending from the'i'orwar'd face'ofthe guideway 52 is a pin 13 uponwhich'one end of alink 'M is pivotally mounted. The other end portion ofthe link bi is provided with'an aperture "l'5'ntered by a crank-pin 'ofacrazik "VVw'hic-h 'is mounted upon an 'end'portioh oan oscillatorylooper-carrying shaft '18. 'Set screws 'I9 secure the crank 'il rigidly:uponth'e "shaft '18. The inner end lportion of thes'haft 15 is mountedin the bearing t3 andthe outer end portion thereof is similarly'mountedin a bearing bracket "80 secured byscrewsl to the underside 'of the`clothplate i6. A thrust/collar 8'2 secured Yuponfthe shaft 18 by screws83 engages the bearing i3 to cooperate with the hub portion of the crank'il' in preventing endwise movements of the shaft '58. Screws 84 securethe looper-carrier 85, carrying the loop-takers or lcopers 35, to thelooper carrying or oscillatory shaft 15. In the p-resent case, theloopers 85 are of the non-thread carrying or single-thread chain-stitchtype.

As may be best seen from Figs. 2 and 3, the bearing 43 is mounted withinthe bearing block or bracket 81 and secured therein by means of a setscrew 88. The bracket in turn is removably secured directly to theunderside of the base I5 by means of screws 89.

y Fromthe above description it is to be understood that the bracket 55carries substantially the entire louper-actuating mechanism and that thebracket in turn is merely secured upon the bearing 37. As may be seenfrom Fig. l, the upper surface of the bracket 55V engages the underside`of the cloth-plate i6, whereby the bracket is prevented from turningabout the axis of the shaft 35.

In order to remove the loopers and their actuating lmechanism from thesewing machine one need only remove the brackets 57 and 80 from themachine base, loosen screws 'E3 from the crank 'Il' so -that'thersh'af-t'i8 `may be removed therefrom, and the'nby-loo'sening the screws 56 and'le the mainfbracket 55 maybe backed oif from the bearing '37. VI-t-isobvious ythat such an operation requires merelytheluse 'of the'sim'plesttools and the eXpendi-ture'of Vonlyva few moments time.

As-the straightline reciprocatory rod Si shifts endwise 'of itself, due-to rotation of the rotary crank 69, the lower end of the link 'Eli iscarried back and forth, thus swinging the link about the crank-#pin v'I6l'of -the 'crank TI, thereby forcing the crank Tl to voscillateabouttheaxis of and in turn to "oscillatethe shaft i8. As may be bestseenfrom-'Figs -7 to 10 inclusive, the crank Tl' and the link 'E4 form atoggle connection and when thesetwo elements are substantially at rightangles'to'each othenias seen in Fig. 8, the link M swings about-'thecrank-pin v'l5 of the crank without appreciablyihoving vthe same. Thus adwell is produce'din the oscillatory'movement of the crank TI andconsequently inthe loopers 8E. Furthermore, it is to be seen from Fig.8, that when the toggle elementsfare perpendicular to each other the-slide-block I2 is at one of its two dead center points thuscausing afurther dwell in theftoggle mechanism. These two dwells are additive asthey occur'at the same point, and the result is that an extremely longperiod of dwell isf-produced in the looperswhen they are atthe end oftheir loop-seizing stroke, as illustratedin the view of a looper'anditscooperating needle shownin Fig. 8. -Theneedle atthis period in thecycle-isatthe-top portion'of its stroke.

Figs. 7, 8 and `9 illustrate three successive stages during thedwell-producing portion of a single revolution ofthe'rotary crank 69.The

r arrows 58 indicate the path Aand the direction of circular movement of-theslide-block '52. It may be seen from Fig. 7 that the suse-mock i2 isapproaching "a dead rcenter 'point and that Athe toggle elements Hand'ITa're approaching their right angle positions and thus the dwellperiod has started. In Fig. 8 vas hereinabovenotedthe slide-block is atone of its two dead center positions vand vthe toggle elements aresubstantially perpendicularwith each other. Fig. 9'illustrates themechanism just at the end of the dwell period when the slide-block haspassed through its dead center position and the toggle elements are nolonger in their perpendicular relation. It is to be seen that verylittle movement has been transmitted to the looper-actuating shaft fromthe rotary crank during this period, and further, that the rotary crankhas passed through a relatively large angle.

It is to be seen that when the slide-block 12 moves from its positionshown in Fig. 9 to that shown in Fig. l0, the reciprocatory bar 6I willbe moved to the right thus imparting an accelerated motion to the toggleelements. The eiiect of this acceleration on the part of the toggleelements is `to accelerate the retracting stroke of the loopers, thushastening the shedding of the needle-loop and giving the descendingneedle more time to shorten such loop. In machines of the single-threadchain-stitch type, it is desirable that the needle-loop be shed from thelooper as quickly as possible after such loop has been entered by thedescending needle, so that the remaining portion of the down-stroke ofthe needle will be suflicient to shorten the shed needle-loop. It is tobe understood that in4 ahnost all single-thread chain-stitch machines,including the present device, the threadcarrying needle is adapted topull thread from the previously formed needle-loop as the needledescends into the work, and thus during the latter portions of thedescending needle movements this loop is shortened suiiiciently to setthe same into the work. Therefore the above described accelerated motionof the looper is timed to occur just after the needle has entered theloop, thereby to insure a quick shedding action of the needle-loop afterthe needle has entered the same. Fig. l illustrates the relativepositions of the elements just before the loop-seizing stroke of theloopers.

The means for lubricating a portion of the looper-actuating mechanism isonly illustrated in Figs. 4, 5 and '7, as it would otherwise complicatethe other gures to include it therein and no useful purpose wouldbeaccomplished thereby. This lubricating means includes the oil conduit4| which delivers oil through a duct 90, provided in the frame l5, to atransverse duct 9| which is provided in the shaft 35 and which registerswith duct 9B twice during every revolution of the shaft 35 thereby topick up oil therefrom. This oil is then delivered to the conduit 92formed longitudinally of the shaft 35 and communicating with a radialduct 93 formed in the rotary crank 69. As the oil is driven under apressure supplied by the oil pump unit 38, it nds its way from theradial duct 93 to another longitudinal conduit 94 formed in the rotarycrank E9 and extending into the crank-pin 'H so as to communicate with atransverse duct 95 also formed in the crank-pin 1I. The oil which isdelivered to the duct 95 is under suicient pressure so that it will findits way about the slide-block 12 to thus lubricate the guideway 62. Theslide-block 12 is provided with horizontally disposed ducts 95 whichwill be aligned with the duct 95 periodically to thus deliver a quantityof the oil to conduits 9G formed in each of the two portions of thereciprocatory rod 6| which extend away from the guideway 62. Theconduits 96 deliver the oil to the transverse ducts 91 which in turndeliver it to the relatively moving surfaces between the iiangedbearings 58 and the rod 6I.

Having thus set forthV the nature of the invention what I claim hereinis:

1. A thread-manipulator mechanism for sewing machines comprisinga rotaryshaft, a pair of xed and spaced bearing members, a straight linereciprocating member mounted in said bearing members, means carried bysaid rotary shaft for imparting simple harmonic motion to saidreciprocating member, a loop-taker, and operative connections betweensaid loop-taker and said reciprocating member, said connectionsincluding crank and link elements of which one is carried by saidreciprocating member and the other is connected to said loop-taker.

2. A sewing machine looper mechanism comprising, a. rotary shaft, astraight line reciprocating member, means including interengaging crankand guideway elements disposed between said rotary shaft and saidreciprocating member for imparting simple harmonic motion to the lattermember, a loop-taker, and operative connections between said loop-takerand said reciprocating member, said connections including crank and linkelements of which one is carried by said reciprocating member and theother is connected to said loop-taker.

3. A sewing machine looper mechanism comprising, a rotary shaft, astraight line reciprocating member, operative connections between saidrotary shaft and said reciprocating member for` imparting simpleharmonic motion to said reciprocating member, said operative connectionsincluding interengaging rotary crank and guideway elements, aloop-taker, and means interposed between said reciprocating member andsaid loop-taker for actuating the latter, said means includinginterconnected crank and link elements one of which is carried by saidreciprocating member and the other is connected to said loop-taker, saidinterconnected crank and link elements being arranged to be disposedsubstantially at right angles to each other when said rotary crank is atone of its two deadcenter points relative to said guideway.

4. A sewing machine looper mechanism comprising, a rotary shaft, arotary crank carried and actuated by said rotary shaft, a straight linereciprocating member, said reciprocating member being formed with aguideway lengthwise extending at right angles to the longitudinal axisof said reciprocating member, said rotary crank being in engagement withsaid guideway for imparting simple harmonic motion to said reciprocatingmember, an oscillatory loop-taker, and means carried by saidreciprocating member and connected to oscillate said loop-taker, saidrotary crank being arranged to be at one of its two dead-center pointsrelative to said guideway when said loop-taker is at the end of itsloop-seizing stroke.

5. A sewing machine looper mechanism comprising, a rotary shaft, arotary crank carried and actuated by said rotary shaft, a straight linereciprocating member, said reciprocating member carrying a guidewaylengthwise extending at right angles to the longitudinal axis of saidmember, said rotary crank being in engagement with said guideway forimparting simple harmonic motion to said reciprocating member, aloop-taker, and operative means connecting said reciprocating member andsaid loop-taker, said operative means including interconnected crank andlink elements which are arranged to be disposed substantially at rightangles to each other when said rotary crank is at one of its twodead-:center 'Ipoin'ts relative 'to lsaid reciprocating member.

v"6. -In ya sewing .fina'cnn'e having la base-porticnincluding'a'cloth-plate, Aare'tar.ysna'ft carried l'b'y said'base-portion and beneath said cloth-plate', a 'straight `.line`reciproca'ting member kdisposed beneath 'said lcloth-.plata'me'anscarried fby said rotary'sha'ft Vfor "imparting Asimple harmonic'Tinotion Ito said reciprocatingrmember, 'anoscillatory looper-carryingshaft disposed in parallel irelation with said A'rotary'shaf-t, alooper, 'a Tlinkle'lement vhaving lone 'end thereof ipivotally secureddirectly to said reciprocating -member, and la crank carried by saidrlooper-carrying shaft "and connected to said link element.

7. In a sewing machine having a base portion including a cloth-plate, arotary shaft carried within said base portionand beneath saidclothplate, a rotary crank carried by said shaft, La

straight line reciprocating 'member disposed "bey neath saidcloth-platefand being adapted to move in simple vharmonic motion,'thelongitudinal axis of said rotary shaft and said reciprocating memberbeing contained in the same plane, said yreciprocating member being'provided with afguide- Way lengthwise extending at right angles to `thelongitudinal axis of said member, said rotary crank being :in operativeengagement with said guideWay,-for reciprocating-said member, a looper,'an oscillatory looper-carrying shaft disposed in parallel `relationwithsaid '.rotary shaft, and means connecting said reciprocating memberVto said looper-carrying shaft, said means including a -toggledevicecausing the looper to have a prolonged -d-well at'the end of itsloop-seizing stroke.

8. A single-thread chain-stitch `sewing machine comprising a frameincluding a base, a rotary shaft jcurnaled inisaid base, atleast onebearing removably secured to said base, an oscillatory shaftmounted insaid bearing and being disposed in rparallel relation with 'said rotaryshaft, a non-thread carrying looper mounted upon saidoscillatory shaft,a bracket-removably secured to said base, looper-actuating mechanismcarried by said bracket, said looper-actui ating mechanism being adaptedto be connected to 'said roscillatory shaft, and means carried by saidrotary `shaft for engaging and actuating said looper-actuatingmechanism.

9. A single-thread chain-stitch sewing machine Acomprising a frameincluding a base, fa rotaryshaft .journaled in said base, an oscillatoryshaft mounted within `said base iand fdisposedin parallel relation withsaid rotary shaft, a non-thread carrying looper carried `on saidoscillatory shaft, a'bracket.'removably'secured to the 'underside io'f'said ibase and llafording :a lbearing-support, an oscillatory'looper-actuating mechanism carried by :said bracket, saidlooperactuating mechanism including a straight Aline reciprocatorymember and toggle meansactuated by said reciprocatorymember'and adaptedto be connected to said oscillatory shaft, and means carried by saidrotary shaft fore'ngaging and imparting 'simple harmonic motionto saidreciprocatorymember.

510. A thread-manipluator mechanism for sewing machines, comprising, avrotary :shaft,`apair of 'xed and spaced bearing members, 'a straightline reciprocating member mounted in said bearing members, means carried-loyl said 'rotary shaft for imparting simple harmonic motion to saidreciprocating member, an oscillatory iloopel, and operative 'connectionsbetween said looper and said reciprocating member, 'said connectionsVincluding means for 'producing #a dwell in the movement `of theloop-taker, the period of "said dwell occurring whenever thereciprocatory member reaches one of .its two direction-changing points.

11. A thread-manipulator mechanismfor sewing "machines, comprising, arotary shaft, 'a pair of iixed and spaced bearing members, fa'straigltline reciprocating member mounted'in 'said -bearing Vmembersgsaiolreciprocating member and the iongitudinal axis of saidirotary shaftbeing contained in the sameplanameans carried by'said rotaryfshaft forimparting :simple harmoniclmotion to saidrecprocatingimemben anoscillatory looper, and operative connections between said looper andsaid reciprocating member, said iconneet-ions including means forproducing a dwell in the movementof'the loop-taker.

l2. In a sewing machinefhaving abase-portion including a cloth-.plataarotaryshaftlcarried by said base-portion and beneath said cloth-plate, astraight line reciprocating member v.disposed beneath said cloth-plate,the vlongitudinal .axes of said rotary shaft andsaid reciprocating:member being vcontained in the sameplane, means carried by said rotaryshaft for imparting simple harmonic 'motion to said `reciprocatingmember, an oscillatory looper-carryingfshaft disposed in parallelrelation with said rotary shaft, a looper, a link element having oneendthereof connected to said reciprocating member, and -a crank carriedby said looper-carrying shaft and-connected to said link element, saidlink :element being arranged to be substanti'allyiat right'angles tosaid crank when `said reciprocating member reaches one of its twodirection-changingpoints.

ANDREWB. CLAYTON.

